In recent years, there is being developed a vehicular pop-up hood device that pushes up a rear end portion of a hood when a vehicle collides with a collision body such as a pedestrian to receive the collision body with the hood and reduce an impact in a viewpoint of pedestrian protection etc.
In a vehicular pop-up hood device disclosed in patent document 1 (Japanese Patent Application Publication No. 2014-133535), actuators are arranged at both sides of a rear end portion of a hood. The actuators are activated at a collision or the like with a collision body, and push up a rear portion of the hood. The actuators each include a cylinder, a piston in the cylinder, a piston rod continuous to the piston, a gas generator, etc. When the gas generator is activated, the piston is pushed up, and the piston rod protrudes upward. The piston is pushed up until the piston comes into contact with a stopper portion (in patent document 1, referred to as front end wall portion) at an upper portion of the cylinder.
FIG. 3 and Paragraph [0023] in patent document 1 describe that the vehicular pop-up hood device (a hood panel flip-up device) is attached to a vehicle body member (a hood ridge reinforcement) through a bracket having a U-like cross-sectional shape. To be specific, the cylinder of the vehicular pop-up hood device is sandwiched between the bracket having the U-like cross-sectional shape and the hood ridge reinforcement of the vehicle body, and the bracket is fixed to the hood ridge reinforcement by bolts.
Patent document 2 (Japanese Patent Application Publication No. 2009-79761) describes that a vehicular pop-up hood device is entirely covered with a coating by fluorocarbon resin coating.
With the attachment structure like patent document 1, in which the vehicular pop-up hood device is attached by sandwiching the cylinder of the vehicular pop-up hood device between the bracket having the U-like cross-sectional shape and the hood ridge reinforcement of the vehicle body and by fixing the bracket to the hood ridge reinforcement by the bolts, it is required to firmly restrain a motion of the cylinder in the up-down direction when the vehicular pop-up hood device is activated. Hence, it is required to strongly sandwich and hold the cylinder between the bracket and the hood ridge reinforcement, to increase the strength and rigidity of the bracket, and to increase a cramping force of the bolts, resulting in an increase in cost.
Also, since the stopper portion (the front end wall portion) is required to strongly receive the piston when the piston comes into contact with the stopper portion, coupling between the stopper portion and the cylinder is required to be strong, resulting in an increase in cost.